"Some say wrong time, wrong place. Alan was volunteering with his Muslim friends to help the people of Syria. He was in the right place doing the right thing."

The wife of IS hostage Alan Henning has made an emotional appeal to his captors[PA]

I ask Islamic State please release him, we need him back home

Barbara Henning

The former taxi driver, from Salford, was taken hostage last December by IS militants.

His life was threatened by a believed British militant - dubbed 'Jihadi John' - in the video showing the brutal murder of Mr Haines.

Mrs Henning last week said she had received an audio message of her husband pleading for his life.

She had also been told that a Sharia court had found him innocent of being a spy.

In her latest statement, she said: "I have a further message for Islamic State: We've not abandoned Alan and we continue in our attempts to communicate with you.

"I have had no contact from Islamic State holding Alan other than an audio file of him pleading for his life."

Barbara Henning made the appeal in her first public appearance since her husband was captured [PA]

She added: "We are at a loss why those leading Islamic State cannot open their hearts and minds to the truth about Alan's humanitarian motives for going to Syria and why they continue to ignore the verdicts of their own justice system.

"Surely those who wish to be seen as a state will act in a statesmanlike way by showing mercy and providing clemency.

"I ask again, supported by the voices across the world, for Islamic State to spare Alan's life.

"Alan, we miss you and we're dreadfully concerned for your safety. But we are given so much hope by the outcry across the world as to your imprisonment."

Alan Henning had his life threatened in the video showing David Haines' beheading [AFP]

IS also released a propaganda video last night appearing to show photojournalist John Cantlie, who is another British hostage.

The clip shows the Briton sitting at a desk and wearing an orange jumpsuit that other IS hostages have also been seen in.

He describes himself as "long-term prisoner" and criticises US president Barack Obama for using air strikes on IS targets.

Mr Cantlie concludes the video by saying: "Join me again for the next programme."